The present invention relates to a wet deasher consisting of a trough filled with quench water. The trough is arranged underneath the ash hopper of a boiler, and is provided with a quench water feed as well as overflow. The trough accommodates ash conveying equipment. Cooling equipment through which the quench water is permanently circulated by means of a pump, is arranged between the overflow and the quench water feed. One or several packs of oblique, parallel plates is/are arranged within the trough before the overflow, according to German Patent Application No. P 28 30 380.20.
One embodiment of this wet deasher has, as cooling equipment, a separate tubular heat exchanger through which the quench water is circulated. After having passed the separator plates the quench water contains only a certain quantity of finest solids having a grain size of minus 0.1 mm and a sinking velocity which is much slower than 1 mm/min.
The design of the cooling equipment must ensure that the flow velocity of the quench water is higher than the sinking velocity of the particles and is so high as to prevent also deposition.
Furthermore the particles sinking by inevitable turbulences shall be returned directly to the pump without remaining in the cooling equipment. The present invention pursues the object of subjecting a wet deasher according to German Patent Application No. P 28 30 380.2 to a further development, so that these requirements are met and, moreover, the physical design of the wet deasher plant is simplified.
Another object of the present invention is to provide an arrangement of the foregoing character which is substantially simple in construction and may be economically fabricated.
A further object of the present invention is to provide an arrangement which may be easily maintained in service and which has a substantially long operating life.